JP4081576B2 - Method for forming electroless plating film, replacement catalyst solution used therefor, printed wiring board, and heat dissipation plating member - Google Patents
Method for forming electroless plating film, replacement catalyst solution used therefor, printed wiring board, and heat dissipation plating member Download PDFInfo
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- JP4081576B2 JP4081576B2 JP2003173450A JP2003173450A JP4081576B2 JP 4081576 B2 JP4081576 B2 JP 4081576B2 JP 2003173450 A JP2003173450 A JP 2003173450A JP 2003173450 A JP2003173450 A JP 2003173450A JP 4081576 B2 JP4081576 B2 JP 4081576B2
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- 239000003054 catalyst Substances 0.000 title claims description 168
- 238000000034 method Methods 0.000 title claims description 144
- 238000007772 electroless plating Methods 0.000 title claims description 129
- 238000007747 plating Methods 0.000 title claims description 96
- 230000017525 heat dissipation Effects 0.000 title claims description 7
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- 239000010949 copper Substances 0.000 claims description 78
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- 239000000084 colloidal system Substances 0.000 claims description 4
- KDLHZDBZIXYQEI-UHFFFAOYSA-N palladium Substances [Pd] KDLHZDBZIXYQEI-UHFFFAOYSA-N 0.000 description 38
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- XLOMVQKBTHCTTD-UHFFFAOYSA-N Zinc monoxide Chemical compound [Zn]=O XLOMVQKBTHCTTD-UHFFFAOYSA-N 0.000 description 2
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- KCXVZYZYPLLWCC-UHFFFAOYSA-N EDTA Chemical compound OC(=O)CN(CC(O)=O)CCN(CC(O)=O)CC(O)=O KCXVZYZYPLLWCC-UHFFFAOYSA-N 0.000 description 1
- 229910018104 Ni-P Inorganic materials 0.000 description 1
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- 238000005238 degreasing Methods 0.000 description 1
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- PIBWKRNGBLPSSY-UHFFFAOYSA-L palladium(II) chloride Chemical compound Cl[Pd]Cl PIBWKRNGBLPSSY-UHFFFAOYSA-L 0.000 description 1
- OFNHPGDEEMZPFG-UHFFFAOYSA-N phosphanylidynenickel Chemical compound [P].[Ni] OFNHPGDEEMZPFG-UHFFFAOYSA-N 0.000 description 1
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- HKZLPVFGJNLROG-UHFFFAOYSA-M silver monochloride Chemical compound [Cl-].[Ag+] HKZLPVFGJNLROG-UHFFFAOYSA-M 0.000 description 1
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Description
【０００１】
【発明の属する技術分野】
本発明は、プリント基板やＡｌ−ＳｉＣ複合素材などの被めっき面として金属材料部と非導電性材料部とを有する基材の非導電性材料部上に無電解めっき皮膜を形成する方法、その方法に用いるのに好適な置換触媒溶液、並びに上記無電解めっき皮膜の形成方法を用いて作製されたプリント配線基板及び放熱めっき部材に関する。
【０００２】
【従来の技術】
近年、電子部品分野など様々な分野において、被めっき面が金属材料部と非導電性材料部とからなる基材上への無電解めっき皮膜を形成することが行われている。
【０００３】
例えば、電子部品分野で使用されるプリント基板は、回路となる銅と基板素材である樹脂とで構成されており、この基板上に、無電解銅めっきなどの無電解めっき皮膜を形成する。
【０００４】
また、ヒートシンク等の放熱板となる放熱めっき部材も、近年では、ＳｉＣ等の非導電性材料からなる多孔体に、銅やアルミニウムが含浸されたような基材が用いられており、当該基材上に、はんだ濡れ性付与を目的として、無電解ニッケルめっき皮膜を形成する。
【０００５】
上記のような基材上へ無電解めっき皮膜を形成する場合、基材の被めっき面に非導電性材料部が存在しているため、触媒金属を付与することが必要であり、従来からセンシタイジング−アクチベーティング法、キャタリスト法、アルカリキャタリスト法、キャタリスティング−アクセレレーティング法などが用いられている。
【０００６】
しかし、近年、形成される無電解めっき皮膜に要求される様々な皮膜特性は更に厳しさを増しており、上述したような従来の触媒金属を付与する方法を単に用いただけでは、その要求を満たすことができなかった。
【０００７】
その理由は、基材の被めっき面が非導電性材料部と金属材料部とが混在した状態となっているためであると考えられる。つまり、異なる材料上へ触媒付与処理や無電解めっき処理を施すが、非導電性材料部と金属材料部とでは、各処理の反応性等が異なり、それぞれの材料部上へ形成される触媒層や無電解めっき皮膜に微妙な差が生じ、これが原因となって皮膜特性が悪くなると考えられる。
【０００８】
例えば、上述したヒートシンク部材を作製する場合においては、形成された無電解ニッケルめっき皮膜にボイドが発生したり、均一性が悪かったりするため、はんだ濡れ性が悪くなるという欠点や耐熱性が悪いという欠点を有している。
【０００９】
また、電子部品分野のプリント基板においては、スルホールやビアホール壁に無めっきが生じるという欠点を有している。更には、形成した回路の電気抵抗が悪い、皮膜外観にムラが生じる、最終的に形成される厚付用の電気銅めっき皮膜と無電解銅めっき皮膜間の密着性が悪いという欠点を有する。
【００１０】
【特許文献１】
特開２００１−１３１７６０号公報
【００１１】
【発明が解決しようとする課題】
本発明は、上記事情に鑑みなされたもので、被めっき面が金属材料部と非導電性材料部とから構成されている複合基材に対して、無めっき現象もなく、密着性の良好な無電解めっき皮膜を形成でき、放熱めっき部材、プリント配線基板等の作製に好適な無電解めっき皮膜の形成方法、それに用いる置換触媒溶液、プリント配線基板、及び放熱めっき部材を提供することを目的とする。
【００１２】
【課題を解決するための手段及び発明の実施の形態】
本発明者らは、上記目的を達成するため鋭意検討した結果、被めっき面が金属材料部と非導電性材料部とで構成される基材に対して、上記金属材料部、非導電性材料部それぞれに対して、触媒付与処理を別途行い、かつ両材料部上に対して同時に（両材料部上への触媒金属付与をコントロールした基材を、無電解めっき浴に浸漬して、両材料上へ一括で）無電解めっき皮膜を形成することが有効であると着想し、置換触媒溶液という上記金属材料部へ触媒付与をすることを目的とする触媒付与工程と、従来からの非導電性材料部上への触媒付与をすることを目的とした触媒付与工程とを組み合わせることで、容易に各種特性に優れた無電解めっき皮膜を形成できることを知見した。
【００１３】
また、特に、プリント配線基板を作製するにあたり、上記両触媒付与工程によって銅（金属材料部）上に付与される触媒金属量をある一定範囲内とすることで、電子部品という特に要求の高い分野においても、高い要求を満たすことができることを知見し、本発明をなすに至った。
【００１４】
従って、本発明は下記の無電解めっき皮膜の形成方法、それに用いる置換触媒溶液、並びにプリント配線基板及び放熱めっき部材を提供する。
請求項１：
被めっき面として金属材料部及び非導電性材料部を有する基材に対し、無電解めっき皮膜を形成する方法であって、
前記金属材料部上に置換触媒溶液を用いて、前記金属材料部に置換析出して前記無電解めっきの触媒となるＡｕ、Ｐｔ、Ｐｄ、Ａｇ、Ｎｉ、Ｃｏ、Ｃｕ、Ｚｎから選ばれる１種又は２種以上の触媒金属を付与する第１触媒工程を行い、続いて
前記非導電性材料部に触媒溶液を用いて前記無電解めっきの触媒となる触媒金属を付与する工程として、（１）酸性Ｐｄ−Ｓｎコロイド溶液で処理する方法、（２）酸性Ｐｄ−Ｓｎコロイド溶液で処理した後、酸溶液で処理する方法、又は（３）Ｐｄ、Ａｇ、Ｐｔ、Ａｕ、Ｎｉ、Ｃｏから選ばれる１種又は２種以上の触媒金属のアルカリ性の触媒金属イオン溶液で処理した後、還元剤液で処理する方法による第２触媒工程を行い、その後
無電解めっき液を用いて、前記金属材料部及び非導電性材料部に同時に無電解めっき皮膜を形成する無電解めっき工程を行うことを特徴とする無電解めっき皮膜の形成方法。
請求項２：
被めっき面として銅である金属材料部、及び樹脂又はセラミックである非導電性材料部を有するプリント配線基板に対し、無電解めっき皮膜を形成する方法であって、
前記金属材料部上に置換触媒溶液を用いて、前記金属材料部に置換析出して前記無電解めっきの触媒となるＰｄ、Ｐｔ、Ａｕ、Ｎｉ、Ｃｏから選ばれる１種又は２種以上の触媒金属を付与する第１触媒工程を行い、続いて
前記非導電性材料部に触媒溶液を用いて前記無電解めっきの触媒となる触媒金属を付与する工程として、（３）Ｐｄ、Ａｇ、Ｐｔ、Ａｕ、Ｎｉ、Ｃｏから選ばれる１種又は２種以上の触媒金属のアルカリ性の触媒金属イオン溶液で処理した後、還元剤液で処理する方法による第２触媒工程を行い、その後
無電解めっき液を用いて、前記金属材料部及び非導電性材料部に同時に無電解めっき皮膜を形成する無電解めっき工程を行うことを特徴とする請求項１記載の無電解めっき皮膜の形成方法。
請求項３：
前記第１触媒工程における触媒金属がＰｄであることを特徴とする請求項２記載の無電解めっき皮膜の形成方法。
請求項４：
前記第２触媒工程における（３）の方法の触媒金属がＰｄであることを特徴とする請求項２又は３記載の無電解めっき皮膜の形成方法。
請求項５：
前記第２触媒工程後において、前記プリント配線基板の銅部分に付着した触媒金属量が１０〜１２０μｇ／ｄｍ 2 であることを特徴とする請求項２乃至４のいずれか１項に記載の無電解めっき皮膜の形成方法。
請求項６：
前記無電解めっき工程が、無電解銅めっき液を用いて無電解銅めっき皮膜を形成する工程であることを特徴とする請求項２乃至５のいずれか１項に記載の無電解めっき皮膜の形成方法。
請求項７：
前記無電解めっき工程が、錯化剤として非アミン系化合物を含有し、アミン系錯化剤を使用せず、ホルムアルデヒドを還元剤とする無電解銅めっき液を用いて無電解銅めっき皮膜を形成する工程であることを特徴とする請求項６記載の無電解めっき皮膜の形成方法。
請求項８：
前記無電解めっき工程が、錯化剤としてロッシェル塩を含有する無電解銅めっき液を用いて無電解銅めっき皮膜を形成する工程であることを特徴とする請求項６記載の無電解め っき皮膜の形成方法。
請求項９：
Ａｌである金属材料部、及び樹脂又はガラスセラミックである非導電性材料部からなる放熱めっき部材用複合材料に、無電解めっき皮膜を形成する方法であって、
前記金属材料部上にＺｎ置換触媒溶液を用いてＺｎである触媒金属を付与する第１触媒工程を行い、続いて
前記非導電性材料部に触媒溶液を用いて前記無電解めっきの触媒となる触媒金属を付与する工程として、（２）酸性Ｐｄ−Ｓｎコロイド溶液で処理した後、酸溶液で処理する方法、又は（３）Ｐｄ、Ａｇ、Ｐｔ、Ａｕ、Ｎｉ、Ｃｏから選ばれる１種又は２種以上の触媒金属のアルカリ性の触媒金属イオン溶液で処理した後、還元剤液で処理する方法による第２触媒工程を行い、その後
無電解めっき液を用いて、前記金属材料部及び非導電性材料部に同時に無電解めっき皮膜を形成する無電解めっき工程を行うことを特徴とする請求項１記載の無電解めっき皮膜の形成方法。
請求項１０：
Ｃｕである金属材料部、及び樹脂又はガラスセラミックである非導電性材料部からなる放熱めっき部材用複合材料に、無電解めっき皮膜を形成する方法であって、
前記金属材料部上にＰｄ置換触媒溶液を用いてＰｄである触媒金属を付与する第１触媒工程を行い、続いて
前記非導電性材料部に触媒溶液を用いて前記無電解めっきの触媒となる触媒金属を付与する工程として、（２）酸性Ｐｄ−Ｓｎコロイド溶液で処理した後、酸溶液で処理する方法、又は（３）Ｐｄ、Ａｇ、Ｐｔ、Ａｕ、Ｎｉ、Ｃｏから選ばれる１種又は２種以上の触媒金属のアルカリ性の触媒金属イオン溶液で処理した後、還元剤液で処理する方法による第２触媒工程を行い、その後
無電解めっき液を用いて、前記金属材料部及び非導電性材料部に同時に無電解めっき皮膜を形成する無電解めっき工程を行うことを特徴とする請求項１記載の無電解めっき皮膜の形成方法。
請求項１１：
前記無電解めっき工程が、無電解ニッケルめっき液を用いて無電解ニッケルめっき皮膜を形成する工程であることを特徴とする請求項９記載の無電解めっき皮膜の形成方法。
請求項１２：
前記無電解めっき工程が、無電解ニッケル−リンめっき液を用いて無電解ニッケル−リンめっき皮膜を形成した後、無電解ニッケル−ボロンめっき液を用いて無電解ニッケル−ボロンめっき皮膜を形成する工程であることを特徴とする請求項９又は１０記載の無電解めっき皮膜の形成方法。
請求項１３：
前記第２触媒工程における（３）の方法の触媒金属がＰｄであることを特徴とする請求項９乃至１２のいずれか１項に記載の無電解めっき皮膜の形成方法。
請求項１４：
前記置換触媒溶液が、アミン化合物を含有しないことを特徴とする請求項１乃至１３のいずれか１項に記載の無電解めっき皮膜の形成方法。
請求項１５：
請求項１４記載の無電解めっき皮膜の形成方法に用いる置換触媒溶液であって、アミン化合物を含有しないことを特徴とする置換触媒溶液。
請求項１６：
請求項２乃至８のいずれか１項に記載の無電解めっき皮膜の形成方法を用いて作製されたことを特徴とする無電解めっき皮膜が形成されたプリント配線基板。
請求項１７：
請求項９乃至１３のいずれか１項に記載の無電解めっき皮膜の形成方法を用いて作製されたことを特徴とする放熱めっき部材。
【００１５】
この場合、特に、プリント基板の無電解めっき方法については、銅張りプリント基板→銅面上にＰｄ置換→スルホール（樹脂部）にアルカリ性のＰｄイオン溶液でＰｄ付与→還元剤液での処理→ロッシェル塩を錯化剤とする無電解銅めっきという工程、方法が好適に採用し得、放熱部材の無電解めっき方法については、Ａｌ−ＳｉＣ複合素材の基体→Ａｌ上にＺｎ置換→ＳｉＣ上にアルカリ性のＰｄイオン溶液でＰｄ付与→還元剤液での処理→無電解ニッケルめっきという工程、方法が好適に採用し得る。
【００１６】
以下、本発明につき更に詳しく説明する。
本発明の無電解めっき皮膜の形成方法は、金属材料部及び非導電性材料部とを有する基材に、必要により適宜な前処理を行った後、第１触媒工程、第２触媒工程を順次行い、最後に無電解めっき工程を行うものである。
【００１７】
（Ｉ）基材
基材としては、被めっき面が、非導電性材料部と金属材料部とからなる基材であれば特に制限はなく、非導電性材料部が樹脂、セラミック等で形成されたもの、金属材料部が各種金属で形成されたものが挙げられるが、本発明は、金属材料部が例えばＣｕやＡｌ等の空気中で酸化し易い金属で形成されたものが有効に用いられる。また、形状も制限はなく、板状、シート状、粉粒状、成形品などが挙げられる。
【００１８】
この場合、基材としては、ヒートシンク等の放熱部材、プリント配線基板などが好適なものとして挙げられる。
【００１９】
ここで、ヒートシンク等の放熱部材において、非導電性材料としては、ＳｉＣなどのガラスセラミックや樹脂が採用できる。金属としては、ＡｌやＣｕなどが挙げられるが、これに制限されない。特には、ガラスセラミックの多孔体又は網状構造体に、ＡｌやＣｕを含浸させたものを好適に採用できる。形状としては、板状、シート状、粉粒体等、制限はない。
【００２０】
一方、プリント配線基板を作製する場合、被めっき面に、銅部分を有する基材が挙げられる。基材は、樹脂製（エポキシ樹脂、ポリイミド樹脂など）、セラミック製などであり、被めっき面は、上記樹脂部分／セラミック部分と銅部分の２種が混在しても、銅部分が、表面の全面であってもよい。この場合、樹脂部分はスルホールやビアホール部分である。形状は、板状、シート状等であってもよい。
【００２１】
なお、上記銅部分は、無電解めっきや電気めっきやスパッタリング等の乾式めっきで形成されていてもよく、銅箔を貼って形成されていてもよい。
【００２２】
具体的には、特にスルホールやビアホールを有する銅張りプリント基板（両面板、多層板、ビルドアップ基板など）を挙げることができる。
【００２３】
（ＩＩ）前処理
上記基材の前処理としては、脱脂、表面調整工程などがあり、基材の種類、使用目的等に応じた公知の前処理法を採用し得る。ヒートシンク等の放熱めっき部材を作製するための基材の洗浄には、超音波洗浄を行うことが好ましい。
【００２４】
（ＩＩＩ）第１触媒工程
第１触媒工程は、上記基材の金属材料部上に触媒となる金属の水溶性塩を含有する置換触媒溶液を用いて触媒金属を付与する工程であって、本工程は基本的に複合基材中の金属に触媒を付与することを目的としており、非導電性材料へは触媒が付与されない。上記置換触媒溶液は、置換法により基材の金属材料部上に触媒金属を付与するもので、当該置換触媒溶液は、アミン化合物を含有しないことが好ましい。アミン化合物を含有していると、触媒溶液の持ち込みや基材表面に付着するなどして、次の第２触媒溶液中にアミン化合物が混入し、第２触媒工程での触媒溶液中の触媒金属をアミン化合物が錯化してしまい、非導電性材料部に触媒が付与されないおそれがあり、その結果形成される無電解めっき皮膜にボイドや無めっきが生じるおそれがある。触媒となる金属としては、Ａｕ、Ｐｔ、Ｐｄ、Ａｇ、Ｎｉ、Ｃｏ、Ｃｕ、Ｚｎなどが挙げられ、当該触媒となる金属は、上記基材の金属材料部の金属種に応じて、適宜置換析出するものを選択する。また、１種であっても、２種以上であってもよい。
【００２５】
例えば、放熱めっき部材を形成する場合、その複合基材の金属部がＡｌである場合はＺｎ、Ｃｕである場合はＰｄが好適なものとして選ばれる。
この場合、Ａｌ金属部に対するＺｎ置換触媒溶液としては、アルミニウムに対してめっきを行う場合に従来から用いられている亜鉛置換めっき液を使用することができる。なお、本発明において、このＺｎ置換触媒溶液の組成としては、Ｚｎイオン１００ｍｇ／Ｌ〜１００ｇ／Ｌ、好ましくは５〜２０ｇ／Ｌ、ｐＨ８以上、好ましくは１０以上（ＮａＯＨ等で調整）であり、ｐＨ１４の強アルカリであってもよい。Ｚｎ塩としては、硝酸亜鉛、酸化亜鉛、硫酸亜鉛等公知のものが採用できる。また処理条件は１０〜３０℃で数秒〜１分間であることが好ましい。
【００２６】
一方、Ｃｕ金属部に対するＰｄ置換触媒溶液としては、Ｐｄイオン１０ｍｇ／Ｌ〜１０ｇ／Ｌ、好ましくは１００〜５００ｍｇ／Ｌ、Ｐｄ塩としては、硫酸塩、硝酸塩、酸化物、塩化物及びそれらの無機複合物、無機酸としては、硫酸、硝酸、塩酸等が使用でき、界面活性剤を添加してもよい。処理条件は２０〜５０℃で１〜１０分間であることが好ましい。
なお、上記Ｚｎ置換触媒溶液、Ｐｄ置換触媒溶液としては、市販品を使用することができる。
【００２７】
また、プリント配線基板を作製する場合の第１触媒工程において、触媒金属としては、Ｐｄ、Ｐｔ、Ａｕ、Ｎｉ、Ｃｏなどの１種又は２種以上が挙げられ、置換触媒溶液は、上記触媒金属の水溶性塩と無機酸を基本組成とする。また、上述したように、上記置換触媒溶液は、アミン系化合物を含有しないことが好ましく、アミン系化合物は、錯化力が強いため、次工程のアルカリキャタリスト法で触媒を付与する場合に、触媒金属の吸着が生じないおそれがあり、スルホールなどの樹脂部に無めっきが生じるおそれがある。その他、界面活性剤や各種添加剤を添加してもよい。
【００２８】
具体的には、この場合の置換触媒溶液の組成としては、公知のＰｄ触媒溶液を用いることができる。Ｐｄ塩としては、硫酸塩、硝酸塩、酸化物、塩化物及びそれらの無機複合物、無機酸としては、硫酸、硝酸、塩酸等が使用でき、界面活性剤を添加してもよい。Ｐｄイオンとしては、例えばＰｄイオン１０ｍｇ／Ｌ〜１０ｇ／Ｌが好ましい。処理条件は通常の処理条件を採用できるが、第１、第２触媒工程終了後の銅上のＰｄ置換量を１０〜１２０μｇ／ｄｍ2、好ましくは２０〜９０μｇ／ｄｍ2となるように処理することが好ましい。
【００２９】
なお、この第１触媒工程は、次の第２触媒工程より先に行うことが重要である。例えば、放熱めっき部材を作製する場合に、第２触媒工程は吸着現象での触媒付与であるため、第１触媒工程が後であると吸着した触媒が流失してしまい、ボイドが発生し易い、皮膜の平滑性が悪くなる、放熱性用途の利用度が悪くなる、はんだ濡れ性が悪くなるという問題が生じる。
【００３０】
また、プリント配線基板を作製する場合も、第１触媒工程を第２触媒工程のアルカリキャタリスト法の後で行うと、第２触媒工程でスルホール等の樹脂部やセラミック部に付与された触媒金属が流失し、樹脂部やセラミック部に無めっきが生じたりするおそれがある。
【００３１】
（ＩＶ）第２触媒工程
この第２触媒工程は、水溶性金属塩を含有する触媒溶液を用いて、吸着現象によって基材の非導電性材料部に触媒金属を付与する工程である。この場合、この触媒金属は、上記金属材料部にも付着してよい。
【００３２】
本第２触媒工程としては、次の３方法を採用できる。
（１）酸性Ｐｄ−Ｓｎコロイド溶液で処理する方法。
（２）酸性Ｐｄ−Ｓｎコロイド溶液で処理した後、酸溶液で処理する方法。
（３）アルカリ性の触媒金属イオン溶液で処理した後、還元剤液で処理する方法。
上記３つの方法のうち、どれを利用するかはそれぞれが持つ特徴をもとに、例えば、基材への侵食や形成される無電解めっき皮膜に要求される特性などへの影響を考慮して選択すればよい。この場合、上記方法は以下の特徴を有する。
（１）と（２）の方法は、（３）の方法に比較して、非導電性材料部上、金属材料部上へ付与される触媒金属量が多い。
（１）と（２）の方法は、Ｓｎが付着する。
（２）の方法は、（１）の方法に比較して、Ｓｎの付着量が少ない。
（３）の方法は、金属材料部上へ付着する触媒金属量が少ない。
（３）の方法は、Ｓｎが付着しない。
この第２触媒工程としては、ヒートシンク等の放熱めっき部材を作製する際は、下記の方法が挙げられる。
（２）酸性Ｐｄ−Ｓｎコロイド溶液で処理した後、酸溶液で処理する方法。
（３）アルカリ性の触媒金属イオン溶液で処理した後、還元剤液で処理する方法。
特に、（３）の方法が好ましい。
一方、プリント配線基板を作製する際は、第２触媒工程は、アルカリ性の触媒金属イオン溶液での処理が好ましい。
【００３３】
ここで、上記（１）、（２）の酸性Ｐｄ−Ｓｎコロイド溶液としては、公知の酸性Ｐｄ−Ｓｎコロイドキャタリスト溶液が使用し得、市販品を用いてもよい。また、（２）の方法における酸溶液としては、塩酸溶液、硫酸溶液等の公知のアクセレレーター酸溶液が使用し得る。更に、（１）、（２）の方法を行う場合の処理条件としては、公知の方法が採用し得る。
【００３４】
一方、（３）の方法において、触媒金属としては、Ｐｄ、Ａｇ、Ｐｔ、Ａｕ、Ｎｉ、Ｃｏなどが挙げられ、これらの１種又は２種以上を使用することができる。
【００３５】
この場合、このアルカリ性触媒金属イオン溶液としては、上記触媒金属水溶性塩を金属、特にパラジウムとして０．０１〜１０ｇ／Ｌ、特にプリント基板を処理する場合には５０〜５００ｍｇ／Ｌ、好ましくは１００〜３００ｍｇ／Ｌ含有し、ｐＨが８〜１１であるものを使用することができる。この溶液は公知のものでよく、市販品を使用することができる。また、処理条件は公知の条件を採用でき、通常２０〜６５℃で１〜１０分の浸漬条件とすることができる。
【００３６】
なお、特にプリント配線基板を作製する際、第１及び第２触媒工程が終了した時点で、基材の銅部分上に付着した触媒金属量は、１０〜１２０μｇ／ｄｍ2（特には２０〜９０μｇ／ｄｍ2）とすることが好ましい。この触媒金属量は、第１触媒工程で付与された触媒金属＋第２触媒工程で付与された触媒金属の合計である。
【００３７】
１０μｇ／ｄｍ2未満であると、基材の銅部分上に無電解銅めっき皮膜が形成されないおそれがあり、スルホール等の樹脂部に無めっきが発生する、銅皮膜が変色するなどが生じるおそれがある。一方、１２０μｇ／ｄｍ2より多いと、回路の短絡が発生するおそれがある。また、無電解銅めっき皮膜の密着性が悪くなるおそれがある。
【００３８】
（Ｖ）還元剤液での処理工程
この工程は、上記第２触媒付与工程において、（３）のアルカリ性触媒金属イオン溶液で処理した場合に、その後工程として行うもので、主として付与された触媒の金属化を目的として行うものである。また、場合によっては、複合基材中の金属材料に形成された酸化皮膜を除去する役割を果たしたり、基材の銅部分を活性化する役割を果たす。
【００３９】
還元剤液での処理は、次の３方法を採用できる。
（１）還元剤液で処理する。
（２）還元剤液で処理した後、特開２００１−１３１７６０号公報記載の還元剤と界面活性剤とを含み、ｐＨ調整剤によりｐＨを１〜７に調整した活性化溶液で、活性化処理を行う。
（３）上記活性化溶液で処理する。
上記のうち、（１）、（２）の工程が好ましく、特にプリント配線基板を作製する場合は、銅部分上により確実に無電解銅めっき皮膜を形成できるため、無電解銅めっき皮膜が形成されない又は形成されるまでに時間がかかるのを防止でき、銅の変色、樹脂部の無めっきを防止することができる点から（２）の工程が好ましい。
【００４０】
なお、上記（１）、（２）の還元剤液は、公知の還元剤を含有する溶液であればよい。
【００４１】
還元剤としては、ジメチルアミンボラン（ＤＭＡＢ）や水素化ホウ素化合物等のボラン系還元剤、ヒドラジン、ホルムアルデヒド等が挙げられる。なお、還元剤の濃度は０．１〜１０ｇ／Ｌ、特に１〜３ｇ／Ｌで、ｐＨは３〜１２、特に３〜５であることが好ましい。また、この還元剤液での処理条件は、２０〜４０℃で１〜１０分の浸漬条件とすることができる。また、上記活性化溶液も同様の処理条件とすることができる。
【００４２】
（ＶＩ）無電解めっき工程
無電解めっき工程では、無電解めっき皮膜を形成する。
無電解めっきの種類は、特に制限はなく、無電解Ｎｉ−Ｐ、無電解Ｎｉ−Ｂ、無電解Ｃｏ、無電解Ｃｕ、無電解Ａｇ、無電解Ａｕ、無電解Ｓｎ、各種合金めっき、無電解複合めっき等が挙げられ、公知の組成のめっき液を用いて公知の条件でめっきを行うことができる。
【００４３】
この場合、放熱板やヒートシンク等を作製する場合には、通常無電解ニッケル−リンめっき液で処理した後、無電解ニッケル−ボロンめっき液で処理することが好ましい。
【００４４】
また、プリント配線基板を作製する場合には、無電解銅めっきが好ましい。この場合、この無電解めっき液としては、錯化剤としてロッシェル塩等の非アミン系錯化剤を用い、アミン系錯化剤を使用していないホルムアルデヒドを還元剤とするタイプのものが好ましい。
【００４５】
なお、上記無電解めっき皮膜は、厚さ０．１〜２．０μｍ、特に０．３〜１．０μｍとすることができるが、これに制限されるものではない。
【００４６】
本発明によれば、被めっき面に非導電性材料と金属材料が混在していても、密着性や均一性などの皮膜特性に優れた無電解めっき皮膜を形成することができる。
【００４７】
例えば、基材が複合素材からなる複合基材であっても、密着性がよく、ボイドの発生がなく、均一な無電解めっき皮膜を形成することができ、特に、電子部品が実装される放熱板のような放熱めっき部材を作製する上で好適に用いることができ、はんだ濡れ性が良好であり、放熱特性に優れた放熱めっき部材を得ることができる。
【００４８】
また、特に、プリント基板を処理する場合において、被めっき面の銅部分、スルホール等の樹脂部分両方に良好な無電解銅めっき皮膜を形成できる上、回路形成においても絶縁樹脂中にＰｄなどが混入することを防げ、信頼性の高い回路基板を作製することができる。
【００４９】
更に、アミン系錯化剤を用いずに無電解銅めっき皮膜を形成するときに、めっき反応が瞬時に開始し、無めっきの発生を防止できる。また、基材の銅部分が長時間空気に晒されても、めっき反応が開始するため、使用する生産ライン（装置）に制限が少ない。しかも、アミン類の廃液処理が必要なく、工業上の利用に有利である上、コスト面でも有利である。また、ロッシェル塩のような錯化力の弱い錯化剤を使用した無電解銅めっき液を用いても、上記利点が得られる。
【００５０】
更には、置換触媒溶液処理の諸条件を変更することで、容易に被めっき面の銅部分に付着する触媒金属量を制御できる。
【００５１】
本発明において、置換触媒溶液は、アルカリキャタリスト法での触媒付与に悪影響を及ぼさず、被めっき面に樹脂部やセラミック部がある場合にも、本発明の無電解めっき皮膜の形成方法を用いたときの効果を確実に得ることができる。
【００５２】
更に、本発明の方法によりプリント基板を得る場合、例えば、ロッシェル塩などの非アミン系錯化剤を使用した無電解銅めっき液を用いて無電解銅めっき皮膜を形成する場合に、プリント基板が長時間空気中に晒されても確実にめっき反応を開始することができる、そのため、生産に使用されるラインや装置への制限が少ない。また、電子回路を形成する場合に、回路の短絡や電気抵抗の悪化を招くことがない上、電気銅めっき皮膜と無電解銅めっき皮膜との密着性を向上させることができるため、高密度化しても信頼性の高い回路基板を得ることができる。
【００５３】
【実施例】
以下、実施例と比較例を示し、本発明を具体的に説明するが、本発明は下記の実施例に制限されるものではない。
【００５４】
［実施例１］
複合基材としてＡｌ−ＳｉＣ複合基材を用い、下記工程に従って無電解めっきを行った。形成された無電解めっき皮膜のボイドの有無、はんだ濡れ性、密着性について評価を行った。結果を表１に示す。
［実施例２］
実施例１において、（６）亜鉛置換の工程後、下記工程を行い、その後（７）アルカリキャタリスト工程を行ったこと以外は、実施例１と同様に処理した。得られた無電解めっき皮膜のボイドの有無、はんだ濡れ性、密着性について評価を行った。結果を表１に示す。
（６’）亜鉛置換 Ｚｎイオン１６ｇ／Ｌ，ＮａＯＨ１４０ｇ／Ｌ，強アルカ性，１５℃，９０秒
（６’’）酸洗浄 硝酸８００ｍｌ／Ｌ，室温，３０秒
【００５６】
［比較例１］
実施例１において、（７）アルカリキャタリスト工程と（８）レデューサー工程を行わなかったこと以外は、実施例１と同様に処理した。得られた無電解めっき皮膜のボイドの有無、はんだ濡れ性、密着性について評価を行った。結果を表１に示す。
【００５７】
［比較例２］
実施例１において、（６）亜鉛置換工程を行わなかったこと以外は、実施例１と同様に処理した。得られた無電解めっき皮膜のボイドの有無、はんだ濡れ性、密着性について評価を行った。結果を表１に示す。
【００５８】
【表１】
［実施例３］
１９０ｍｍ×１４０ｍｍ×３ｍｍに研削加工されたＳｉＣ多孔体にＡｌを含浸させたＡｌ−ＳｉＣ複合基材（ＳｉＣ；４０体積％）を、実施例１と同様に処理し、ＩＧＢＴ用放熱基板を作製した。得られた放熱基板表面にはんだペーストをスクリーン印刷し、当該はんだペースト上にＳｉ3Ｎ4からなるセラミック基板を載置し、３００℃のリフロー炉で５分間加熱処理してセラミック基板を接合させた。
【００６０】
このセラミック基板を接合した放熱基板を、厚さ２０ｍｍのＡｌ板にボルトにより固定し、−４０℃〜＋１２５℃を１サイクルとして１，０００サイクルの冷熱サイクル試験を行った。試験後、はんだ層の破壊、熱流路の遮断はみられなかった。
【００６１】
［実験例１，２、比較実験例１〜６］
基材として銅箔を使用し、銅箔をエッチング液によって銅を数μｍ溶解し、水洗後、酸による洗浄を行い、水洗後、２５℃で２分間酸濃度０．１ＮとしたＰｄ置換触媒溶液（ＰｄＣｌ2：表２に示す濃度，ＨＣｌ：０．１Ｎ）に浸漬し、水洗後、６０℃で５分間アルカリ性Ｐｄイオン触媒溶液（Ｐｄイオン０．２ｇ／Ｌ，キレート剤０．０１Ｍ，ｐＨ１１）に浸漬し、水洗を行い、３５℃で３分間還元剤液（ＤＭＡＢ２ｇ／Ｌ）に浸漬し、水洗を行い、２５℃で１分間活性化溶液（特開２００１−１３１７６０号公報に記載の活性化溶液）に浸漬し、ロッシェル塩タイプのホルムアルデヒドを還元剤とした無電解銅めっき液（上村工業（株）製スルカップＰＥＡ）中に浸漬する工程を標準工程とし、表２に示すように実施した。
【００６２】
無電解銅めっき浴中において、析出電位測定を行い、銅上のめっき反応性の差異を確認した。なお、析出電位評価方法としては、Ａｇ／ＡｇＣｌ参照電極を使用したとき、銅箔を無電解銅めっき浴に浸漬した後、瞬時に−８００ｍＶ以上に達した場合を合格（○）とし、それ未満を不合格（×）とした。
【００６３】
【表２】
以上から、実験例１，２のようにＰｄ置換析出を行った場合、１８０秒間銅箔が空気中に晒されても、瞬時に銅箔上に無電解銅のめっき反応が開始することがわかる。
一方、比較実験例１〜５のようにＰｄ置換析出を行わない場合、活性化処理を行うと、銅箔が空気中に晒される時間が増えてもめっき反応が開始するが、６０秒間銅箔が空気中に晒されると、めっき反応が瞬時に開始しなくなることがわかる。
上記から、本発明の処理方法によれば、ＥＤＴＡ等のアミン系錯化剤を用いなくとも、長時間空気に晒された銅上で瞬時に無電解めっき反応が開始するので、生産性が高くなる。また、装置を非酸化性雰囲気下においたりするなどの必要がなく、経済的である。更には、アミン化合物の廃液処理も必要ないので、コスト面でも有利である。
【００６５】
【０００１】
［実施例４〜１３、比較例３，４］
基材として市販のＦＲ−４銅張り積層板を使用し、該基板を公知のエッチング液を用いて銅を数μｍ溶解した。その後、水洗し、Ｐｄ置換析出を表３に示す条件で行った以外は、実験例１，２と同様の前処理を行った。この処理後の基板の銅上のＰｄ付着量を測定した。これら基板を３６℃で３０分間ロッシェル塩タイプのホルムアルデヒドを還元剤とした無電解銅めっき液（上村工業（株）製スルカップＰＥＡ）中に浸漬して、無電解銅めっき皮膜を基板の銅上及びスルホール壁に形成した。その後、公知の硫酸銅電気めっき液を用いて３０μｍの銅めっき皮膜を形成し、１５０℃で１時間熱処理を施した。無めっきの有無、無電解銅めっき皮膜と電気銅めっき皮膜間の密着性を確認した。結果を表３に示す。
【００６６】
また、無めっきの有無は、スルホール断面をＳＥＭにより確認し、無めっき部がある場合を不合格（×）、無めっき部がない場合を合格（○）とした。
無電解銅めっき皮膜と電気銅めっき皮膜間の密着性の評価は、上記基板から引き剥がした銅箔（ＦＲ−４銅張り積層基板の表面層の銅、無電解銅めっき皮膜及び電気銅めっき皮膜がめっき処理により重なったもの）にバーナー熱衝撃試験法を用いて、該銅箔が炎により赤くなった時点で炎から該銅箔を離し、放置冷却後、銅箔にふくれが生じた場合を不合格（×）、ふくれが生じない場合を合格（○）とした。
【００６７】
【表３】
以上から、本発明の方法を用いてプリント配線基板を作製した場合、その信頼性が高いことがわかる。また、被めっき面の銅部分上のＰｄ付着量が少なすぎると無めっきの発生が生じることがわかる。更には、被めっき面の銅部分上のＰｄ付着量が多すぎると無電解銅めっき皮膜自体の形成には何ら問題はないが、その後の電気銅めっき皮膜との密着性が悪くなることがわかる
【００６９】
【発明の効果】
本発明によれば、被めっき面が金属材料部と非導電性材料部とから構成されている複合基材に対して、無めっき現象もなく、密着性の良好な無電解めっき皮膜を形成できる。[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a method for forming an electroless plating film on a non-conductive material portion of a substrate having a metal material portion and a non-conductive material portion as a surface to be plated such as a printed circuit board or an Al-SiC composite material, A displacement catalyst solution suitable for use in the process,AndMade using the above electroless plating film formation methodPrinted wiring board andHeat dissipation plating materialRelatedTo do.
[0002]
[Prior art]
In recent years, in various fields such as an electronic component field, an electroless plating film is formed on a substrate whose surface to be plated is composed of a metal material portion and a non-conductive material portion.
[0003]
For example, a printed circuit board used in the electronic component field is composed of copper as a circuit and resin as a substrate material, and an electroless plating film such as electroless copper plating is formed on the substrate.
[0004]
In addition, a heat-dissipating plated member serving as a heat-dissipating plate such as a heat sink has recently been used as a base material in which a porous body made of a non-conductive material such as SiC is impregnated with copper or aluminum. On top of this, an electroless nickel plating film is formed for the purpose of imparting solder wettability.
[0005]
When an electroless plating film is formed on a substrate as described above, a non-conductive material portion is present on the surface of the substrate to be plated, so it is necessary to apply a catalytic metal. The tapping-activating method, the catalyst method, the alkaline catalyst method, the catalysting-accelrating method and the like are used.
[0006]
However, in recent years, various film properties required for the electroless plating film to be formed have become more severe, and the above-described conventional method of applying a catalytic metal can be used simply to satisfy the requirement. I couldn't.
[0007]
The reason is considered to be because the surface to be plated of the base material is in a state where the non-conductive material portion and the metal material portion are mixed. In other words, a catalyst application process or an electroless plating process is performed on different materials, but the reactivity of each process is different between the non-conductive material part and the metal material part, and the catalyst layer formed on each material part. It is thought that subtle differences occur in the electroless plating film and the film characteristics deteriorate due to this.
[0008]
For example, in the case of producing the heat sink member described above, voids are generated in the formed electroless nickel plating film or the uniformity is poor, so that the solder wettability is poor and the heat resistance is bad. Has drawbacks.
[0009]
Moreover, printed circuit boards in the field of electronic components have the disadvantage that no plating occurs on the through hole and via hole walls. Furthermore, there are drawbacks in that the formed circuit has poor electrical resistance, uneven coating appearance, and poor adhesion between the finally formed thick electrolytic copper plating film and the electroless copper plating film.
[0010]
[Patent Document 1]
JP 2001-131760 A
[0011]
[Problems to be solved by the invention]
The present invention has been made in view of the above circumstances, and there is no non-plating phenomenon and good adhesion to a composite substrate whose surface to be plated is composed of a metal material portion and a non-conductive material portion. An electroless plating film can be formed, a method for forming an electroless plating film suitable for the production of a heat radiating plating member, a printed wiring board, etc., a replacement catalyst solution used therefor,Printed wiring board, andHeat dissipation plating partMaterialThe purpose is to provide.
[0012]
Means for Solving the Problem and Embodiment of the Invention
As a result of intensive studies to achieve the above object, the present inventors have found that the metal material part and the nonconductive material are compared with a base material whose surface to be plated is composed of a metal material part and a nonconductive material part. For each part, a catalyst application treatment is performed separately, and on both material parts at the same time (both materials are immersed in an electroless plating bath with a controlled catalyst metal addition on both material parts. Inspired by the fact that it is effective to form an electroless plating film (in a lump up), a catalyst application step for applying a catalyst to the metal material part, which is a substitution catalyst solution, and conventional non-conductivity It has been found that an electroless plating film excellent in various properties can be easily formed by combining with a catalyst application step for applying a catalyst on the material part.
[0013]
In particular, in the production of a printed wiring board, the amount of catalyst metal applied on copper (metal material part) by both the catalyst application processes is within a certain range, so that there is a particularly high demand for electronic components. However, the present inventors have found that high demands can be satisfied, and have made the present invention.
[0014]
Accordingly, the present invention provides a method for forming the following electroless plating film, a replacement catalyst solution used therefor, andPrinted wiring board andHeat dissipation plating partMaterialprovide.
Claim 1:
For a base material having a metal material part and a non-conductive material part as a plated surface,A method of forming an electroless plating film,
SaidUsing substitution catalyst solution on metal material part1 or 2 or more types selected from Au, Pt, Pd, Ag, Ni, Co, Cu, and Zn, which are substituted and deposited on the metal material portion to serve as the electroless plating catalystPerforming a first catalytic step of applying catalytic metal, followed by
SaidUsing a catalyst solution for the non-conductive material partBecome a catalyst for the electroless platingAdd catalytic metalThe steps include (1) a method of treating with an acidic Pd—Sn colloidal solution, (2) a method of treating with an acidic Pd—Sn colloidal solution and then treating with an acid solution, or (3) Pd, Ag, Pt, Au, According to a method of treating with an alkaline catalyst metal ion solution of one or more catalyst metals selected from Ni and Co and then treating with a reducing agent solution.Perform the second catalyst step, then
Using electroless plating solutionThe metal material part and the non-conductive material part simultaneouslyA method of forming an electroless plating film, comprising performing an electroless plating process for forming an electroless plating film.
Claim 2:
A method of forming an electroless plating film on a printed wiring board having a metal material portion that is copper as a surface to be plated and a non-conductive material portion that is resin or ceramic,
One or more types of catalysts selected from Pd, Pt, Au, Ni, and Co that are used as a catalyst for electroless plating by substitution deposition on the metal material part using a substitution catalyst solution on the metal material part Performing the first catalytic step of applying metal, followed by
(3) One or two types selected from Pd, Ag, Pt, Au, Ni, and Co as a step of applying a catalytic metal serving as a catalyst for the electroless plating using a catalyst solution to the non-conductive material portion After the treatment with the alkaline catalyst metal ion solution of the above catalyst metal, the second catalyst step is carried out by the treatment with the reducing agent solution, and then
2. The method of forming an electroless plating film according to claim 1, wherein an electroless plating process is performed for simultaneously forming an electroless plating film on the metal material part and the non-conductive material part using an electroless plating solution. .
Claim 3:
The method for forming an electroless plating film according to claim 2, wherein the catalyst metal in the first catalyst step is Pd.
Claim 4:
The method for forming an electroless plating film according to claim 2 or 3, wherein the catalyst metal in the method (3) in the second catalyst step is Pd.
Claim 5:
After the second catalyst step, the amount of catalyst metal adhering to the copper portion of the printed wiring board is 10 to 120 μg / dm. 2 The method for forming an electroless plating film according to any one of claims 2 to 4, wherein the electroless plating film is formed.
Claim 6:
The electroless plating step forms an electroless copper plating film using an electroless copper plating solution.Is a processClaimsIn any one of 2 to 5The formation method of the electroless-plating film of description.
Claim 7:
The electroless plating process contains a non-amine compound as a complexing agent, does not use an amine complexing agent, and forms an electroless copper plating film using an electroless copper plating solution containing formaldehyde as a reducing agent The method for forming an electroless plating film according to claim 6, wherein
Claim 8:
The electroless plating process according to claim 6, wherein the electroless plating step is a step of forming an electroless copper plating film using an electroless copper plating solution containing Rochelle salt as a complexing agent. A method for forming a plating film.
Claim 9:
A method of forming an electroless plating film on a composite material for a heat-dissipating plating member comprising a metal material part made of Al and a non-conductive material part made of resin or glass ceramic,
Performing a first catalyst step of applying a catalytic metal which is Zn using a Zn-substituted catalyst solution on the metal material part,
(2) A method of treating with an acidic Pd—Sn colloidal solution and then treating with an acid solution, as a step of applying a catalytic metal serving as a catalyst for the electroless plating to the nonconductive material part using a catalyst solution, or (3) Second catalyst step by a method of treating with an alkaline catalyst metal ion solution of one or more kinds of catalyst metals selected from Pd, Ag, Pt, Au, Ni, Co and then treating with a reducing agent solution And then
2. The method of forming an electroless plating film according to claim 1, wherein an electroless plating process is performed for simultaneously forming an electroless plating film on the metal material part and the non-conductive material part using an electroless plating solution. .
Claim 10:
A method of forming an electroless plating film on a composite material for a heat-dissipating plated member comprising a metal material part made of Cu and a non-conductive material part made of resin or glass ceramic,
Performing a first catalyst step of applying a catalyst metal which is Pd using a Pd-substituted catalyst solution on the metal material part;
(2) A method of treating with an acidic Pd—Sn colloidal solution and then treating with an acid solution, as a step of applying a catalytic metal serving as a catalyst for the electroless plating to the nonconductive material part using a catalyst solution, or (3) Second catalyst step by a method of treating with an alkaline catalyst metal ion solution of one or more kinds of catalyst metals selected from Pd, Ag, Pt, Au, Ni, Co and then treating with a reducing agent solution And then
2. The method of forming an electroless plating film according to claim 1, wherein an electroless plating process is performed for simultaneously forming an electroless plating film on the metal material part and the non-conductive material part using an electroless plating solution. .
Claim 11:
The method of forming an electroless plating film according to claim 9, wherein the electroless plating step is a step of forming an electroless nickel plating film using an electroless nickel plating solution.
Claim 12:
The electroless plating step includes forming an electroless nickel-phosphorous plating film using an electroless nickel-phosphorous plating solution, and then forming an electroless nickel-boron plating film using an electroless nickel-boron plating solution. The method of forming an electroless plating film according to claim 9 or 10.
Claim 13:
The method for forming an electroless plating film according to any one of claims 9 to 12, wherein the catalyst metal in the method (3) in the second catalyst step is Pd.
Claim 14:
The method for forming an electroless plating film according to claim 1, wherein the substitution catalyst solution does not contain an amine compound.
Claim 15:
A replacement catalyst solution for use in the method of forming an electroless plating film according to claim 14, wherein the replacement catalyst solution does not contain an amine compound.
Claim 16:
A printed wiring board on which an electroless plating film is formed, which is produced by using the electroless plating film forming method according to any one of claims 2 to 8.
Claim 17:
A heat-dissipating plated member produced using the electroless plating film forming method according to claim 9.
[0015]
In this case, in particular, for the electroless plating method of the printed board, copper-clad printed board → Pd substitution on the copper surface → Pd application with alkaline Pd ion solution to the through hole (resin part) → Treatment with reducing agent solution → Rochelle The process and method of electroless copper plating using a salt as a complexing agent can be suitably adopted. Regarding the electroless plating method of the heat radiating member, Al—SiC composite material base → Zn substitution on Al → Alkaline on SiC The process and method of Pd application with a Pd ion solution, treatment with a reducing agent solution, and electroless nickel plating can be suitably employed.
[0016]
Hereinafter, the present invention will be described in more detail.
In the method of forming an electroless plating film of the present invention, a base material having a metal material part and a non-conductive material part is subjected to an appropriate pretreatment if necessary, and then the first catalyst step and the second catalyst process.AboutThese are sequentially performed, and finally the electroless plating process is performed.
[0017]
(I) Substrate
The substrate is not particularly limited as long as the surface to be plated is a substrate composed of a non-conductive material portion and a metal material portion, and the non-conductive material portion is formed of resin, ceramic, etc., metal material Although the part formed with various metals is mentioned, what formed the metal material part with the metal which is easy to oxidize in air, such as Cu and Al, for example is used effectively. Moreover, there is no restriction | limiting also in a shape, A plate shape, a sheet form, a granular form, a molded article, etc. are mentioned.
[0018]
In this case, preferred examples of the base material include a heat radiating member such as a heat sink, and a printed wiring board.
[0019]
Here, in a heat dissipation member such as a heat sink, a glass ceramic such as SiC or a resin can be employed as the non-conductive material. Examples of the metal include Al and Cu, but are not limited thereto. In particular, a glass ceramic porous body or network structure impregnated with Al or Cu can be suitably employed. The shape is not limited, such as a plate shape, a sheet shape, and a granular material.
[0020]
On the other hand, when producing a printed wiring board, the base material which has a copper part in the to-be-plated surface is mentioned. The base material is made of resin (epoxy resin, polyimide resin, etc.), ceramic, etc., and the plated surface is the surface of the copper part even if the resin part / ceramic part and the copper part are mixed. The whole surface may be sufficient. In this case, the resin portion is a through hole or a via hole portion. The shape may be a plate shape, a sheet shape, or the like.
[0021]
In addition, the said copper part may be formed by dry plating, such as electroless plating, electroplating, and sputtering, and may be formed by sticking copper foil.
[0022]
Specifically, a copper-clad printed board (such as a double-sided board, a multilayer board, and a build-up board) having a through hole or a via hole can be given.
[0023]
(II) Pretreatment
Examples of the pretreatment of the substrate include degreasing and a surface adjustment step, and a known pretreatment method corresponding to the type of the substrate, the purpose of use, and the like can be adopted. It is preferable to perform ultrasonic cleaning for cleaning the base material for producing a heat radiating plating member such as a heat sink.
[0024]
(III) First catalyst step
The first catalyst step is a step of applying a catalytic metal using a substitution catalyst solution containing a water-soluble salt of a metal serving as a catalyst on the metal material portion of the base material, and this step is basically a composite group. The purpose is to impart a catalyst to the metal in the material, and no catalyst is imparted to the non-conductive material. The said substitution catalyst solution provides a catalyst metal on the metal material part of a base material by a substitution method, and it is preferable that the said substitution catalyst solution does not contain an amine compound. If it contains an amine compound, the amine compound is mixed into the next second catalyst solution due to bringing in the catalyst solution or adhering to the surface of the substrate, and the catalyst metal in the catalyst solution in the second catalyst step. As a result, the amine compound may be complexed and the catalyst may not be imparted to the non-conductive material portion, and as a result, voids or non-plating may occur in the electroless plating film formed. Examples of the metal serving as a catalyst include Au, Pt, Pd, Ag, Ni, Co, Cu, and Zn, and the metal serving as the catalyst is appropriately substituted depending on the metal type of the metal material portion of the base material. Select what to deposit. Moreover, it may be one type or two or more types.
[0025]
For example, when forming a heat-dissipating plated member, Zn is selected when the metal part of the composite substrate is Al, and Pd is selected when Cu is Cu.
In this case, as the Zn substitution catalyst solution for the Al metal part, a zinc substitution plating solution which has been conventionally used when plating on aluminum can be used. In the present invention, the composition of the Zn substitution catalyst solution is Zn ion 100 mg / L to 100 g / L, preferably 5 to 20 g / L, pH 8 or more, preferably 10 or more (adjusted with NaOH or the like), It may be a strong alkali having a pH of 14. As the Zn salt, known ones such as zinc nitrate, zinc oxide and zinc sulfate can be employed. The treatment conditions are preferably 10 to 30 ° C. and several seconds to 1 minute.
[0026]
On the other hand, as a Pd substitution catalyst solution for Cu metal part, Pd ions are 10 mg / L to 10 g / L, preferably 100 to 500 mg / L., PAs the d salt, sulfates, nitrates, oxides, chlorides and their inorganic composites can be used, and as the inorganic acid, sulfuric acid, nitric acid, hydrochloric acid and the like can be used, and a surfactant may be added. The treatment conditions are preferably 20 to 50 ° C. and 1 to 10 minutes.
In addition, a commercial item can be used as said Zn substitution catalyst solution and Pd substitution catalyst solution.
[0027]
Further, in the first catalyst step in the production of a printed wiring board, examples of the catalyst metal include one or more of Pd, Pt, Au, Ni, Co, etc. The basic composition is a water-soluble salt and an inorganic acid. Further, as described above, the substitution catalyst solution preferably does not contain an amine compound, and the amine compound has a strong complexing power. Therefore, when the catalyst is imparted by the alkaline catalyst method in the next step, There is a possibility that the catalyst metal does not adsorb, and there is a possibility that no plating will occur in the resin part such as a through hole. In addition, surfactants and various additives may be added.
[0028]
Specifically, the composition of the substitution catalyst solution in this case is known asPd Catalyst solution can be used. As the Pd salt, sulfates, nitrates, oxides, chlorides and their inorganic composites can be used, and as the inorganic acid, sulfuric acid, nitric acid, hydrochloric acid and the like can be used, and a surfactant may be added. As Pd ions, for example, Pd ions 10 mg / L to 10 g / LPreferGood. Although normal processing conditions can be adopted as processing conditions, the amount of Pd substitution on copper after the completion of the first and second catalytic steps is 10 to 120 μg / dm.2, Preferably 20 to 90 μg / dm2It is preferable to process so that it may become.
[0029]
It is important that this first catalyst step is performed before the next second catalyst step. For example, when producing a heat-dissipating plated member, since the second catalyst step is catalyst application by an adsorption phenomenon, if the first catalyst step is later, the adsorbed catalyst is washed away, and voids are likely to occur. There arises a problem that the smoothness of the film is deteriorated, the utilization of the heat dissipation application is deteriorated, and the solder wettability is deteriorated.
[0030]
Also, in the case of producing a printed wiring board, if the first catalyst step is performed after the alkaline catalyst method of the second catalyst step, the catalyst metal applied to the resin portion such as a through hole or the ceramic portion in the second catalyst step May be lost, and no plating may occur in the resin part or the ceramic part.
[0031]
(IV) Second catalyst step
This 2nd catalyst process is a process of providing a catalyst metal to the nonelectroconductive material part of a base material by an adsorption phenomenon using the catalyst solution containing a water-soluble metal salt. In this case, the catalyst metal may adhere to the metal material portion.
[0032]
The following three methods can be adopted as the second catalyst step.
(1) A method of treating with an acidic Pd—Sn colloidal solution.
(2) A method of treating with an acid solution after treating with an acidic Pd—Sn colloidal solution.
(3) A method of treating with a reducing agent solution after treating with an alkaline catalyst metal ion solution.
Which of the above three methods is used depends on the characteristics of each method, for example, considering the influence on the characteristics required for the erosion of the base material and the electroless plating film to be formed. Just choose. In this case, the method has the following characteristics.
Compared with the method (3), the methods (1) and (2) have a larger amount of catalytic metal applied to the non-conductive material part and the metal material part.
In the methods (1) and (2), Sn adheres.
The method (2) has a smaller amount of Sn deposited than the method (1).
In the method (3), the amount of catalytic metal adhering to the metal material portion is small.
In the method (3), Sn does not adhere.
As this 2nd catalyst process, the following method is mentioned when producing heat-radiation plating members, such as a heat sink.
(2) A method of treating with an acid solution after treating with an acidic Pd—Sn colloidal solution.
(3) A method of treating with a reducing agent solution after treating with an alkaline catalyst metal ion solution.
In particular, the method (3) is preferable.
On the other hand, when producing a printed wiring board, the second catalyst step is preferably treated with an alkaline catalytic metal ion solution.
[0033]
Here, as the acidic Pd—Sn colloid solution of (1) and (2) above, known acidic Pd—Sn colloid catalyst solutions can be used, and commercially available products may be used. In addition, as the acid solution in the method (2), a known accelerator acid solution such as a hydrochloric acid solution or a sulfuric acid solution can be used. Furthermore, a known method can be adopted as a processing condition when the methods (1) and (2) are performed.
[0034]
On the other hand, in the method (3), examples of the catalytic metal include Pd, Ag, Pt, Au, Ni, Co, and the like, and one or more of these can be used.
[0035]
In this case, the alkaline catalytic metal ion solution is 0.01 to 10 g / L of the above catalytic metal water-soluble salt as a metal, particularly palladium, particularly 50 to 500 mg / L, preferably 100 when processing a printed circuit board. The one containing ~ 300 mg / L and having a pH of 8-11 can be used. This solution may be a known one, and a commercially available product can be used. Moreover, well-known conditions can be employ | adopted for process conditions, and it can be normally set as immersion conditions for 1 to 10 minutes at 20-65 degreeC.
[0036]
In particular, when producing a printed wiring board, the amount of catalyst metal adhering to the copper portion of the base material at the time when the first and second catalyst steps are completed is 10 to 120 μg / dm.2(Especially 20 to 90 μg / dm2) Is preferable. This amount of catalyst metal is the sum of the catalyst metal applied in the first catalyst step + the catalyst metal applied in the second catalyst step.
[0037]
10 μg / dm2If it is less than the range, the electroless copper plating film may not be formed on the copper portion of the substrate, and there is a possibility that non-plating will occur in the resin part such as through-hole, or the copper film may be discolored. On the other hand, 120 μg / dm2If it is more, a short circuit may occur. Moreover, there exists a possibility that the adhesiveness of an electroless copper plating film may worsen.
[0038]
(V) Treatment step with reducing agent solution
This step is performed as a subsequent step in the second catalyst application step when treated with the alkaline catalyst metal ion solution of (3), and is mainly performed for the purpose of metallization of the applied catalyst. Moreover, depending on the case, it plays the role which removes the oxide film formed in the metal material in a composite base material, or the role which activates the copper part of a base material.
[0039]
The following three methods can be adopted for the treatment with the reducing agent solution.
(1) Treat with a reducing agent solution.
(2) After treatment with a reducing agent solution, an activation treatment is performed with an activation solution containing a reducing agent and a surfactant described in JP-A-2001-131760 and having a pH adjusted to 1 to 7 with a pH adjusting agent. I do.
(3) Treat with the activation solution.
Among the above, the steps (1) and (2) are preferable, and in particular, when a printed wiring board is produced, the electroless copper plating film can be more reliably formed on the copper portion, so the electroless copper plating film is not formed. Alternatively, the step (2) is preferable because it can prevent time from being formed and can prevent copper discoloration and non-plating of the resin part.
[0040]
In addition, the reducing agent liquid of said (1) and (2) should just be a solution containing a well-known reducing agent.
[0041]
Examples of the reducing agent include borane-based reducing agents such as dimethylamine borane (DMAB) and borohydride compounds, hydrazine, and formaldehyde. In addition, it is preferable that the density | concentration of a reducing agent is 0.1-10 g / L, especially 1-3 g / L, and pH is 3-12, especially 3-5. Moreover, the process conditions with this reducing agent liquid can be made into the immersion conditions for 1 to 10 minutes at 20-40 degreeC. Also, the activation solution can be set to the same processing conditions.
[0042]
(VI) Electroless plating process
In the electroless plating process, an electroless plating film is formed.
The type of electroless plating is not particularly limited. Electroless Ni-P, electroless Ni-B, electroless Co, electroless Cu, electroless Ag, electroless Au, electroless Sn, various alloy platings, electroless Composite plating etc. are mentioned, It can plate on well-known conditions using the plating solution of a well-known composition.
[0043]
In this case, when producing a heat sink, a heat sink or the like, it is preferable to treat with an electroless nickel-boron plating solution after treatment with an electroless nickel-phosphorus plating solution.
[0044]
Moreover, when producing a printed wiring board, electroless copper plating is preferable. In this case, the electroless plating solution is preferably of a type in which a non-amine complexing agent such as Rochelle salt is used as a complexing agent and formaldehyde that does not use an amine complexing agent is used as a reducing agent.
[0045]
The electroless plating film may have a thickness of 0.1 to 2.0 μm, particularly 0.3 to 1.0 μm, but is not limited thereto.
[0046]
According to the present invention, an electroless plating film excellent in film characteristics such as adhesion and uniformity can be formed even if a non-conductive material and a metal material are mixed on the surface to be plated.
[0047]
For example, even if the base material is a composite base material, it has good adhesion, does not generate voids, and can form a uniform electroless plating film. It can be suitably used for producing a heat radiating plated member such as a plate, and a heat radiating plated member having good solder wettability and excellent heat radiating properties can be obtained.
[0048]
In particular, when processing a printed circuit board, it is possible to form a good electroless copper plating film on both the copper part of the surface to be plated and the resin part such as through hole, and also in the formation of the circuit, Pd and the like are mixed in the insulating resin. Therefore, a highly reliable circuit board can be manufactured.
[0049]
Furthermore, when an electroless copper plating film is formed without using an amine complexing agent, the plating reaction starts instantly, and the occurrence of no plating can be prevented. Moreover, even if the copper part of a base material is exposed to air for a long time, since a plating reaction starts, there are few restrictions on the production line (apparatus) to be used. Moreover, there is no need for waste liquid treatment of amines, which is advantageous for industrial use and advantageous in terms of cost. Further, the above advantages can be obtained even when an electroless copper plating solution using a complexing agent having a weak complexing power such as Rochelle salt is used.
[0050]
Furthermore, the amount of catalytic metal adhering to the copper portion of the surface to be plated can be easily controlled by changing various conditions of the replacement catalyst solution treatment.
[0051]
In the present invention, the substitution catalyst solution does not adversely affect the catalyst application by the alkali catalyst method, and the method for forming an electroless plating film of the present invention is used even when the surface to be plated has a resin part or a ceramic part. It is possible to reliably obtain the effect of being there.
[0052]
Further, when a printed circuit board is obtained by the method of the present invention, for example, when an electroless copper plating film is formed using an electroless copper plating solution using a non-amine complexing agent such as Rochelle salt, the printed circuit board is Even if it is exposed to the air for a long time, the plating reaction can be surely started, so there are few restrictions on the lines and equipment used for production. In addition, when forming an electronic circuit, the circuit is not short-circuited and the electrical resistance is not deteriorated, and the adhesion between the electrolytic copper plating film and the electroless copper plating film can be improved. However, a highly reliable circuit board can be obtained.
[0053]
【Example】
EXAMPLES Hereinafter, although an Example and a comparative example are shown and this invention is demonstrated concretely, this invention is not restrict | limited to the following Example.
[0054]
[Example 1]
An Al—SiC composite substrate was used as the composite substrate, and electroless plating was performed according to the following steps. The formed electroless plating film was evaluated for the presence of voids, solder wettability, and adhesion. The results are shown in Table 1.
[Example 2]
In Example 1, it processed like Example 1 except having performed the following process after the process of (6) zinc substitution, and having performed the alkali catalyst process after that (7). The obtained electroless plating film was evaluated for the presence of voids, solder wettability, and adhesion. The results are shown in Table 1.
(6 ') Zinc substitution Zn ion 16g / L, NaOH 140g / L, strong alkalinity, 15 ° C, 90 seconds
(6 ″) Acid cleaning Nitric acid 800 ml / L, room temperature, 30 seconds
[0056]
[Comparative Example 1]
In Example 1, it processed like Example 1 except not having performed the (7) alkali catalyst process and the (8) reducer process. The obtained electroless plating film was evaluated for the presence of voids, solder wettability, and adhesion. The results are shown in Table 1.
[0057]
[Comparative Example 2]
In Example 1, it processed like Example 1 except not having performed the (6) zinc substitution process. The obtained electroless plating film was evaluated for the presence of voids, solder wettability, and adhesion. The results are shown in Table 1.
[0058]
[Table 1]
[Example 3]
An Al—SiC composite base material (SiC; 40% by volume) impregnated with Al in an SiC porous body ground to 190 mm × 140 mm × 3 mm was treated in the same manner as in Example 1 to produce an IGBT heat dissipation substrate. . A solder paste is screen-printed on the surface of the obtained heat dissipation substrate, and Si is placed on the solder paste.ThreeNFourThe ceramic substrate which consists of this was mounted, and it heat-processed for 5 minutes in a 300 degreeC reflow furnace, and joined the ceramic substrate.
[0060]
The heat dissipation substrate to which this ceramic substrate was bonded was fixed to an Al plate having a thickness of 20 mm with a bolt, and 1,000 cycles of a thermal cycle test were performed with −40 ° C. to + 125 ° C. as one cycle. After the test, the solder layer was not broken and the heat flow path was not blocked.
[0061]
[ExperimentExample1,2CompareExperimentExample1~6]
A copper foil is used as a base material, a copper foil is dissolved by several μm with an etching solution, washed with water, washed with an acid, washed with water, and a Pd-substituted catalyst solution with an acid concentration of 0.1 N for 2 minutes at 25 ° C. (PdCl2: Concentration shown in Table 2, HCl: 0.1N), washed with water, and then immersed in an alkaline Pd ion catalyst solution (Pd ion 0.2g / L, chelating agent 0.01M, pH 11) at 60 ° C for 5 minutes. , Washed with water, immersed in a reducing agent solution (DMAB 2 g / L) at 35 ° C. for 3 minutes, washed with water, and activated at 25 ° C. for 1 minute (activation solution described in JP-A-2001-131760). The step of immersing in an electroless copper plating solution (Urumura Kogyo Sulcup PEA) using Rochelle salt formaldehyde as a reducing agent was a standard step, and was carried out as shown in Table 2.
[0062]
In the electroless copper plating bath, the deposition potential was measured to confirm the difference in plating reactivity on copper. In addition, as a deposition potential evaluation method, when an Ag / AgCl reference electrode is used, a case where it reaches −800 mV or more instantaneously after dipping a copper foil in an electroless copper plating bath is regarded as acceptable (◯), and less than that Was rejected (x).
[0063]
[Table 2]
From the aboveExperimentExample1,2When Pd substitution deposition is performed as described above, it can be seen that even when the copper foil is exposed to the air for 180 seconds, the electroless copper plating reaction starts instantaneously on the copper foil.
Meanwhile, comparisonExperimentExample1~5When Pd substitution deposition is not performed as in the case of performing activation treatment, the plating reaction starts even if the time during which the copper foil is exposed to the air is increased, but when the copper foil is exposed to the air for 60 seconds, It can be seen that the plating reaction does not start instantaneously.
From the above, according to the treatment method of the present invention, since an electroless plating reaction starts instantaneously on copper exposed to air for a long time without using an amine complexing agent such as EDTA, the productivity is high. Become. Moreover, there is no need to place the apparatus in a non-oxidizing atmosphere, which is economical. Furthermore, since the waste liquid treatment of the amine compound is not necessary, it is advantageous in terms of cost.
[0065]
[0001]
[Example4~13Comparative example3,4]
A commercially available FR-4 copper-clad laminate was used as a base material, and copper was dissolved by several μm using a known etching solution. Then, it washed with water and Pd substitution precipitation was performed on the conditions shown in Table 3,ExperimentExample1,2The same pretreatment was performed. The adhesion amount of Pd on the copper after the treatment was measured. These substrates are immersed in an electroless copper plating solution (Sulcup PEA manufactured by Uemura Kogyo Co., Ltd.) using Rochelle salt formaldehyde as a reducing agent at 36 ° C. for 30 minutes, and the electroless copper plating film is placed on the copper of the substrate and Formed on the through-hole wall. Thereafter, a 30 μm copper plating film was formed using a known copper sulfate electroplating solution, and heat treatment was performed at 150 ° C. for 1 hour. The presence or absence of no plating and the adhesion between the electroless copper plating film and the electrolytic copper plating film were confirmed. The results are shown in Table 3.
[0066]
Moreover, the presence or absence of non-plating confirmed the through hole cross section by SEM, made the case where there is an unplated part unsatisfactory (x), and made the case where there is no non-plated part (circle).
The evaluation of adhesion between the electroless copper plating film and the electro copper plating film was carried out using the copper foil peeled off from the substrate (copper on the surface layer of the FR-4 copper-clad laminate, electroless copper plating film and electro copper plating film) When the copper foil turns red due to the flame using the burner thermal shock test method, the copper foil is separated from the flame, and after standing cooling, the copper foil is blistered. A case where a failure (x) or no blistering occurred was determined to be a pass (◯).
[0067]
[Table 3]
From the above, it can be seen that when a printed wiring board is produced using the method of the present invention, its reliability is high. It can also be seen that if the amount of Pd deposited on the copper portion of the surface to be plated is too small, no plating occurs. Furthermore, it is understood that there is no problem in the formation of the electroless copper plating film itself when the Pd adhesion amount on the copper portion of the surface to be plated is too large, but the adhesion with the subsequent electrolytic copper plating film is deteriorated.
[0069]
【The invention's effect】
According to the present invention, an electroless plating film with good adhesion can be formed on a composite base material whose plating surface is composed of a metal material part and a non-conductive material part without any plating phenomenon. .
Claims (17)
前記金属材料部上に置換触媒溶液を用いて、前記金属材料部に置換析出して前記無電解めっきの触媒となるＡｕ、Ｐｔ、Ｐｄ、Ａｇ、Ｎｉ、Ｃｏ、Ｃｕ、Ｚｎから選ばれる１種又は２種以上の触媒金属を付与する第１触媒工程を行い、続いて
前記非導電性材料部に触媒溶液を用いて前記無電解めっきの触媒となる触媒金属を付与する工程として、（１）酸性Ｐｄ−Ｓｎコロイド溶液で処理する方法、（２）酸性Ｐｄ−Ｓｎコロイド溶液で処理した後、酸溶液で処理する方法、又は（３）Ｐｄ、Ａｇ、Ｐｔ、Ａｕ、Ｎｉ、Ｃｏから選ばれる１種又は２種以上の触媒金属のアルカリ性の触媒金属イオン溶液で処理した後、還元剤液で処理する方法による第２触媒工程を行い、その後
無電解めっき液を用いて、前記金属材料部及び非導電性材料部に同時に無電解めっき皮膜を形成する無電解めっき工程を行うことを特徴とする無電解めっき皮膜の形成方法。A method of forming an electroless plating film on a substrate having a metal material part and a non-conductive material part as a surface to be plated ,
With substituted catalyst solution on the metal material portion, the the catalyst of the metal material portion to displace deposition to electroless plating Au, Pt, Pd, Ag, Ni, Co, Cu, 1 kind selected from Zn Or performing a first catalytic step to provide two or more catalytic metals,
As a step of applying a catalyst metal that becomes a catalyst for the electroless plating using a catalyst solution to the non-conductive material part , (1) a method of treating with an acidic Pd-Sn colloid solution, (2) an acidic Pd-Sn colloid A method of treating with an acid solution after treating with a solution, or (3) treating with an alkaline catalytic metal ion solution of one or more kinds of catalytic metals selected from Pd, Ag, Pt, Au, Ni, Co Thereafter, a second catalyst step is performed by a method of treating with a reducing agent solution, and then an electroless plating step of simultaneously forming an electroless plating film on the metal material portion and the nonconductive material portion using the electroless plating solution. A method for forming an electroless plating film characterized by comprising:
前記金属材料部上に置換触媒溶液を用いて、前記金属材料部に置換析出して前記無電解めっきの触媒となるＰｄ、Ｐｔ、Ａｕ、Ｎｉ、Ｃｏから選ばれる１種又は２種以上の触媒金属を付与する第１触媒工程を行い、続いて
前記非導電性材料部に触媒溶液を用いて前記無電解めっきの触媒となる触媒金属を付与する工程として、（３）Ｐｄ、Ａｇ、Ｐｔ、Ａｕ、Ｎｉ、Ｃｏから選ばれる１種又は２種以上の触媒金属のアルカリ性の触媒金属イオン溶液で処理した後、還元剤液で処理する方法による第２触媒工程を行い、その後
無電解めっき液を用いて、前記金属材料部及び非導電性材料部に同時に無電解めっき皮膜を形成する無電解めっき工程を行うことを特徴とする請求項１記載の無電解めっき皮膜の形成方法。Metal material portion is copper as the plated surface, and to a printed wiring board having a non-conductive material portions with a resin or ceramic, a method for forming an electroless plating film,
With substituted catalyst solution on the metal material portion, the the catalyst of the metal material portion to displace deposition to the electroless plating Pd, Pt, Au, Ni, 1 kind or 2 or more catalysts selected from Co Performing the first catalytic step of applying metal, followed by
As a process of applying catalytic metal of said catalyst for electroless plating using the catalyst solution to said non-conductive material portions, (3) Pd, Ag, Pt, Au, Ni, 1 or two elements selected from Co after treatment with alkaline catalyst metal ion solution of more catalytic metals, performing a second catalytic step according to the method of treatment with a reducing agent solution, after the
2. The method of forming an electroless plating film according to claim 1, wherein an electroless plating process is performed for simultaneously forming an electroless plating film on the metal material part and the non-conductive material part using an electroless plating solution. .
前記金属材料部上にＺｎ置換触媒溶液を用いてＺｎである触媒金属を付与する第１触媒工程を行い、続いて
前記非導電性材料部に触媒溶液を用いて前記無電解めっきの触媒となる触媒金属を付与する工程として、（２）酸性Ｐｄ−Ｓｎコロイド溶液で処理した後、酸溶液で処理する方法 、又は（３）Ｐｄ、Ａｇ、Ｐｔ、Ａｕ、Ｎｉ、Ｃｏから選ばれる１種又は２種以上の触媒金属のアルカリ性の触媒金属イオン溶液で処理した後、還元剤液で処理する方法による第２触媒工程を行い、その後
無電解めっき液を用いて、前記金属材料部及び非導電性材料部に同時に無電解めっき皮膜を形成する無電解めっき工程を行うことを特徴とする請求項１記載の無電解めっき皮膜の形成方法。Metal material portion Al is, and the composite material for heat dissipation plating member made of a non-conductive material portions with a resin or glass ceramic, a method for forming an electroless plating film,
Performing a first catalyst applying a catalytic metal is Zn using a Zn-substituted catalyst solution onto the metal material portion, followed by
As a process of applying catalytic metal of said catalyst for electroless plating using the catalyst solution to said non-conductive material portions, (2) is treated with an acidic Pd-Sn colloidal solution, a method of treating an acid solution, or (3) Second catalyst step by a method of treating with an alkaline catalyst metal ion solution of one or more kinds of catalyst metals selected from Pd, Ag, Pt, Au, Ni, Co and then treating with a reducing agent solution was carried out, then using an electroless plating solution, electroless plating according to claim 1, characterized in that the electroless plating step of forming an electroless plated film at the same time the metal material portion and a non-conductive material portions Method for forming a film.
前記金属材料部上にＰｄ置換触媒溶液を用いてＰｄである触媒金属を付与する第１触媒工程を行い、続いてPerforming a first catalyst step of applying a catalyst metal which is Pd using a Pd-substituted catalyst solution on the metal material part;
前記非導電性材料部に触媒溶液を用いて前記無電解めっきの触媒となる触媒金属を付与する工程として、（２）酸性Ｐｄ−Ｓｎコロイド溶液で処理した後、酸溶液で処理する方法、又は（３）Ｐｄ、Ａｇ、Ｐｔ、Ａｕ、Ｎｉ、Ｃｏから選ばれる１種又は２種以上の触媒金属のアルカリ性の触媒金属イオン溶液で処理した後、還元剤液で処理する方法による第２触媒工程を行い、その後(2) A method of treating with an acidic Pd—Sn colloidal solution and then treating with an acid solution, as a step of applying a catalytic metal serving as a catalyst for the electroless plating to the nonconductive material part using a catalyst solution, or (3) Second catalyst step by a method of treating with an alkaline catalyst metal ion solution of one or more kinds of catalyst metals selected from Pd, Ag, Pt, Au, Ni, Co and then treating with a reducing agent solution And then
無電解めっき液を用いて、前記金属材料部及び非導電性材料部に同時に無電解めっき皮膜を形成する無電解めっき工程を行うことを特徴とする請求項１記載の無電解めっき皮膜の形成方法。2. The method of forming an electroless plating film according to claim 1, wherein an electroless plating process is performed for simultaneously forming an electroless plating film on the metal material part and the non-conductive material part using an electroless plating solution. .
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| JP6142964B2 (en) * | 2014-08-28 | 2017-06-07 | 三菱電機株式会社 | Manufacturing method of semiconductor device |
| JP6386310B2 (en) * | 2014-09-05 | 2018-09-05 | Ｄｏｗａメタルテック株式会社 | Pretreatment method for plating Al-Cu joint |
| JP6201153B2 (en) | 2014-09-11 | 2017-09-27 | 石原ケミカル株式会社 | Nickel colloidal catalyst solution for electroless nickel or nickel alloy plating and electroless nickel or nickel alloy plating method |
| CN115135804B (en) * | 2020-02-19 | 2023-12-22 | 学校法人芝浦工业大学 | Plating substrate |
| CN115537788A (en) * | 2022-08-29 | 2022-12-30 | 深圳大学 | Chemical plating activator and preparation method and application thereof |
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